The long range objective of this project is the description of the component molecular events in the replication of the negative strand viruses (myxo, paramyxo, rhabdo, arena and bunya viruses). The topics that are currently being investigated are: 1. The origin of D1 particles. 2. The mechanism of mRNA synthesis in VSV infected cells. 3. Nucleocapsid assembly. This project was transferred from the Laboratory of Molecular Biology.